A number of techniques have been devised to clean, etch, deposit on and/or activate the surface of materials to improve various industrial processes (e.g., coating, gluing, dyeing, printing, lacquering, laminating, etc.). For example, some materials may inherently have poor bonding properties due to their inert or low-energy surfaces. Applying a stream of highly electrically conductive atomically or molecularly charged particles (i.e., positive or negative ions) to a material surface will increase the energy of the surface, and thereby improve its bonding performance. Generally, ionization may be effected by various chemical or physical means, including light interaction, subatomic (electrons, protons, neutrons, positrons, photons, etc.), atomic and/or molecular collisions, and radioactive decay.
Various industrial techniques (e.g., corona, chemical corona, plasma and flame treatments) apply high energy (e.g., via a high frequency power supply) to a process gas (e.g., air or a noble or other gas) to liberate electrons or other charged particles, which at least partially ionize the process gas. The various constituent parts (i.e., various charged and neutral atoms and molecules and various subatomic particles) of the resulting discharge (e.g., corona or plasma) react and collide with the material substrates to alter their surface energies.
Further, various sheet materials, such as paper and polymer webs and films, are often used in printing, coating and laminating applications. Treater stations have been devised to treat the surfaces of such sheet materials in a continuous manner as the material is unwound from its roll. The sheet material is passed through the treater station so that at least one surface passes through the electrical discharge from the electrode assembly, which may include one or more active electrodes that are mounted to the treater station and spaced by a narrow gap from a ground electrode in which the surface treatment occurs.